A mesh frame includes a side frame, wherein the side frame includes a first face in contact with a human body during use, the first face being provided with a recess, the recess obliquely extending towards an inner side of the side frame and configured to snap a mesh to the mesh frame.

A posture detection system for detecting a user's posture according to the embodiments includes a pressure sensor unit, a controller, a feedback mechanism, and a display unit. The pressure sensor unit has a sheet shape or a padded shape and includes plurality of sensors. Each of the sensors is configured to detect a pressure applied from the user. The controller is configured to classify the user's posture based on detection data detected by the pressure sensor unit. The feedback mechanism is configured to provide feedback to the user by vibrating based on a result of the classification. The display unit is configured to perform a display according to the result of the classification.

A seatback shell mounting device removably secures a seatback shell to a seatback frame. The seatback shell includes a support member with a base secured to the seatback shell and an outwardly extending arm with an elbow. The elbow is shaped to mate with an upper seatback frame element. A fastening member has a base secured to the seatback shell and an outwardly extending resilient lever arm with a cam surface and a step formed on an underside. The lever arm is shaped to define an underside cradle. The mounting device facilitates assembly and removal of a seatback shell onto a seatback frame.

A seatback shell mounting device removably secures a seatback shell to a seatback frame. The seatback shell includes a support member with a base secured to the seatback shell and an outwardly extending arm with an elbow. The elbow is shaped to mate with an upper seatback frame element. A fastening member has a base secured to the seatback shell and an outwardly extending resilient lever arm with a cam surface and a step formed on an underside. The lever arm is shaped to define an underside cradle. The mounting device facilitates assembly and removal of a seatback shell onto a seatback frame.

A seating arrangement includes a rigid back frame, a flexible back shell coupled to the back frame and including a pair of vertical side portions and at least two strap portions extending laterally between the side portions and including a forwardly-facing surface configured to support a back of a seated user, the at least two strap portions including a lowermost strap portion, the lowermost strap portion configured to deflect a first distance when a rearwardly-directed force is exerted on the lowermost strap portion by a seated user, and a lumbar assembly supported from the back frame and configured to support the lumbar region of a back of a seated user, the lumbar assembly configured to deflect a second distance when the rearwardly-directed force is exerted on the lumbar assembly by a seated user, wherein the first distance and the second distance are substantially similar.

A piece of seating furniture having a base member, on the upper side of which a padded seat surface is provided, and having at least one backrest member with an upholstered backrest surface, which can be positioned in various positions on the upper side of the base member. A slot structure is provided in the padded seat surface of the base member, which penetrates the padded seat surface, and furthermore a guide member is connected to the backrest member which projects through the upholstered seat surface in the area of the slot structure.

A piece of seating furniture having a base member, on the upper side of which a padded seat surface is provided, and having at least one backrest member with an upholstered backrest surface, which can be positioned in various positions on the upper side of the base member. A slot structure is provided in the padded seat surface of the base member, which penetrates the padded seat surface, and furthermore a guide member is connected to the backrest member which projects through the upholstered seat surface in the area of the slot structure.

A backrest includes a primary frame having a pair of laterally spaced first uprights defining a first opening therebetween, a first front surface and a first rear surface. A secondary frame includes a pair of laterally spaced second uprights defining a second opening therebetween, a second rear surface facing the first front surface of the primary frame and a second front surface, wherein the secondary frame is coupled to the primary frame, and wherein at least portions of the first and second openings are aligned. A flexible shell overlies and is coupled to the second front surface of the secondary frame. The flexible shell includes a third rear surface visible through the aligned portions of the first and second openings.

A backrest includes a primary frame having a pair of laterally spaced first uprights defining a first opening therebetween, a first front surface and a first rear surface. A secondary frame includes a pair of laterally spaced second uprights defining a second opening therebetween, a second rear surface facing the first front surface of the primary frame and a second front surface, wherein the secondary frame is coupled to the primary frame, and wherein at least portions of the first and second openings are aligned. A flexible shell overlies and is coupled to the second front surface of the secondary frame. The flexible shell includes a third rear surface visible through the aligned portions of the first and second openings.

A home or office chair is disclosed having a flexible mesh back rest and a full lumbar back support including upper and lower lumbar supports that are located one above the other at the back of the chair to press against the outside of the mesh back rest. The upper and lower lumbar supports are connected to the back of the chair by a bolt so as to move back and forth in first and opposite directions in response to a user seated in the chair moving his back against and away from the flexible mesh back rest. The upper and lower lumbar supports of the full lumbar back support apply continuous pressure through the mesh back rest to provide support for upper and lower lumbar areas of the user's back regardless of whether the user's back is at rest or pressing against the mesh back rest.